/* * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved. * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the BSD-type * license below: * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * Neither the name of the Network Appliance, Inc. nor the names of * its contributors may be used to endorse or promote products * derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * Author: Tom Tucker */ #include #include #include #include #include #include #include #define RPCDBG_FACILITY RPCDBG_SVCXPRT /* * Replace the pages in the rq_argpages array with the pages from the SGE in * the RDMA_RECV completion. The SGL should contain full pages up until the * last one. */ static void rdma_build_arg_xdr(struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *ctxt, u32 byte_count) { struct rpcrdma_msg *rmsgp; struct page *page; u32 bc; int sge_no; /* Swap the page in the SGE with the page in argpages */ page = ctxt->pages[0]; put_page(rqstp->rq_pages[0]); rqstp->rq_pages[0] = page; /* Set up the XDR head */ rqstp->rq_arg.head[0].iov_base = page_address(page); rqstp->rq_arg.head[0].iov_len = min_t(size_t, byte_count, ctxt->sge[0].length); rqstp->rq_arg.len = byte_count; rqstp->rq_arg.buflen = byte_count; /* Compute bytes past head in the SGL */ bc = byte_count - rqstp->rq_arg.head[0].iov_len; /* If data remains, store it in the pagelist */ rqstp->rq_arg.page_len = bc; rqstp->rq_arg.page_base = 0; /* RDMA_NOMSG: RDMA READ data should land just after RDMA RECV data */ rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base; if (rmsgp->rm_type == rdma_nomsg) rqstp->rq_arg.pages = &rqstp->rq_pages[0]; else rqstp->rq_arg.pages = &rqstp->rq_pages[1]; sge_no = 1; while (bc && sge_no < ctxt->count) { page = ctxt->pages[sge_no]; put_page(rqstp->rq_pages[sge_no]); rqstp->rq_pages[sge_no] = page; bc -= min_t(u32, bc, ctxt->sge[sge_no].length); rqstp->rq_arg.buflen += ctxt->sge[sge_no].length; sge_no++; } rqstp->rq_respages = &rqstp->rq_pages[sge_no]; rqstp->rq_next_page = rqstp->rq_respages + 1; /* If not all pages were used from the SGL, free the remaining ones */ bc = sge_no; while (sge_no < ctxt->count) { page = ctxt->pages[sge_no++]; put_page(page); } ctxt->count = bc; /* Set up tail */ rqstp->rq_arg.tail[0].iov_base = NULL; rqstp->rq_arg.tail[0].iov_len = 0; } /* Issue an RDMA_READ using the local lkey to map the data sink */ int rdma_read_chunk_lcl(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head, int *page_no, u32 *page_offset, u32 rs_handle, u32 rs_length, u64 rs_offset, bool last) { struct ib_rdma_wr read_wr; int pages_needed = PAGE_ALIGN(*page_offset + rs_length) >> PAGE_SHIFT; struct svc_rdma_op_ctxt *ctxt = svc_rdma_get_context(xprt); int ret, read, pno; u32 pg_off = *page_offset; u32 pg_no = *page_no; ctxt->direction = DMA_FROM_DEVICE; ctxt->read_hdr = head; pages_needed = min_t(int, pages_needed, xprt->sc_max_sge_rd); read = min_t(int, (pages_needed << PAGE_SHIFT) - *page_offset, rs_length); for (pno = 0; pno < pages_needed; pno++) { int len = min_t(int, rs_length, PAGE_SIZE - pg_off); head->arg.pages[pg_no] = rqstp->rq_arg.pages[pg_no]; head->arg.page_len += len; head->arg.len += len; if (!pg_off) head->count++; rqstp->rq_respages = &rqstp->rq_arg.pages[pg_no+1]; rqstp->rq_next_page = rqstp->rq_respages + 1; ctxt->sge[pno].addr = ib_dma_map_page(xprt->sc_cm_id->device, head->arg.pages[pg_no], pg_off, PAGE_SIZE - pg_off, DMA_FROM_DEVICE); ret = ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[pno].addr); if (ret) goto err; atomic_inc(&xprt->sc_dma_used); ctxt->sge[pno].lkey = xprt->sc_pd->local_dma_lkey; ctxt->sge[pno].length = len; ctxt->count++; /* adjust offset and wrap to next page if needed */ pg_off += len; if (pg_off == PAGE_SIZE) { pg_off = 0; pg_no++; } rs_length -= len; } if (last && rs_length == 0) set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); else clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); memset(&read_wr, 0, sizeof(read_wr)); ctxt->cqe.done = svc_rdma_wc_read; read_wr.wr.wr_cqe = &ctxt->cqe; read_wr.wr.opcode = IB_WR_RDMA_READ; read_wr.wr.send_flags = IB_SEND_SIGNALED; read_wr.rkey = rs_handle; read_wr.remote_addr = rs_offset; read_wr.wr.sg_list = ctxt->sge; read_wr.wr.num_sge = pages_needed; ret = svc_rdma_send(xprt, &read_wr.wr); if (ret) { pr_err("svcrdma: Error %d posting RDMA_READ\n", ret); set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); goto err; } /* return current location in page array */ *page_no = pg_no; *page_offset = pg_off; ret = read; atomic_inc(&rdma_stat_read); return ret; err: svc_rdma_unmap_dma(ctxt); svc_rdma_put_context(ctxt, 0); return ret; } /* Issue an RDMA_READ using an FRMR to map the data sink */ int rdma_read_chunk_frmr(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head, int *page_no, u32 *page_offset, u32 rs_handle, u32 rs_length, u64 rs_offset, bool last) { struct ib_rdma_wr read_wr; struct ib_send_wr inv_wr; struct ib_reg_wr reg_wr; u8 key; int nents = PAGE_ALIGN(*page_offset + rs_length) >> PAGE_SHIFT; struct svc_rdma_op_ctxt *ctxt = svc_rdma_get_context(xprt); struct svc_rdma_fastreg_mr *frmr = svc_rdma_get_frmr(xprt); int ret, read, pno, dma_nents, n; u32 pg_off = *page_offset; u32 pg_no = *page_no; if (IS_ERR(frmr)) return -ENOMEM; ctxt->direction = DMA_FROM_DEVICE; ctxt->frmr = frmr; nents = min_t(unsigned int, nents, xprt->sc_frmr_pg_list_len); read = min_t(int, (nents << PAGE_SHIFT) - *page_offset, rs_length); frmr->direction = DMA_FROM_DEVICE; frmr->access_flags = (IB_ACCESS_LOCAL_WRITE|IB_ACCESS_REMOTE_WRITE); frmr->sg_nents = nents; for (pno = 0; pno < nents; pno++) { int len = min_t(int, rs_length, PAGE_SIZE - pg_off); head->arg.pages[pg_no] = rqstp->rq_arg.pages[pg_no]; head->arg.page_len += len; head->arg.len += len; if (!pg_off) head->count++; sg_set_page(&frmr->sg[pno], rqstp->rq_arg.pages[pg_no], len, pg_off); rqstp->rq_respages = &rqstp->rq_arg.pages[pg_no+1]; rqstp->rq_next_page = rqstp->rq_respages + 1; /* adjust offset and wrap to next page if needed */ pg_off += len; if (pg_off == PAGE_SIZE) { pg_off = 0; pg_no++; } rs_length -= len; } if (last && rs_length == 0) set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); else clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); dma_nents = ib_dma_map_sg(xprt->sc_cm_id->device, frmr->sg, frmr->sg_nents, frmr->direction); if (!dma_nents) { pr_err("svcrdma: failed to dma map sg %p\n", frmr->sg); return -ENOMEM; } atomic_inc(&xprt->sc_dma_used); n = ib_map_mr_sg(frmr->mr, frmr->sg, frmr->sg_nents, PAGE_SIZE); if (unlikely(n != frmr->sg_nents)) { pr_err("svcrdma: failed to map mr %p (%d/%d elements)\n", frmr->mr, n, frmr->sg_nents); return n < 0 ? n : -EINVAL; } /* Bump the key */ key = (u8)(frmr->mr->lkey & 0x000000FF); ib_update_fast_reg_key(frmr->mr, ++key); ctxt->sge[0].addr = frmr->mr->iova; ctxt->sge[0].lkey = frmr->mr->lkey; ctxt->sge[0].length = frmr->mr->length; ctxt->count = 1; ctxt->read_hdr = head; /* Prepare REG WR */ ctxt->reg_cqe.done = svc_rdma_wc_reg; reg_wr.wr.wr_cqe = &ctxt->reg_cqe; reg_wr.wr.opcode = IB_WR_REG_MR; reg_wr.wr.send_flags = IB_SEND_SIGNALED; reg_wr.wr.num_sge = 0; reg_wr.mr = frmr->mr; reg_wr.key = frmr->mr->lkey; reg_wr.access = frmr->access_flags; reg_wr.wr.next = &read_wr.wr; /* Prepare RDMA_READ */ memset(&read_wr, 0, sizeof(read_wr)); ctxt->cqe.done = svc_rdma_wc_read; read_wr.wr.wr_cqe = &ctxt->cqe; read_wr.wr.send_flags = IB_SEND_SIGNALED; read_wr.rkey = rs_handle; read_wr.remote_addr = rs_offset; read_wr.wr.sg_list = ctxt->sge; read_wr.wr.num_sge = 1; if (xprt->sc_dev_caps & SVCRDMA_DEVCAP_READ_W_INV) { read_wr.wr.opcode = IB_WR_RDMA_READ_WITH_INV; read_wr.wr.ex.invalidate_rkey = ctxt->frmr->mr->lkey; } else { read_wr.wr.opcode = IB_WR_RDMA_READ; read_wr.wr.next = &inv_wr; /* Prepare invalidate */ memset(&inv_wr, 0, sizeof(inv_wr)); ctxt->inv_cqe.done = svc_rdma_wc_inv; inv_wr.wr_cqe = &ctxt->inv_cqe; inv_wr.opcode = IB_WR_LOCAL_INV; inv_wr.send_flags = IB_SEND_SIGNALED | IB_SEND_FENCE; inv_wr.ex.invalidate_rkey = frmr->mr->lkey; } /* Post the chain */ ret = svc_rdma_send(xprt, ®_wr.wr); if (ret) { pr_err("svcrdma: Error %d posting RDMA_READ\n", ret); set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); goto err; } /* return current location in page array */ *page_no = pg_no; *page_offset = pg_off; ret = read; atomic_inc(&rdma_stat_read); return ret; err: ib_dma_unmap_sg(xprt->sc_cm_id->device, frmr->sg, frmr->sg_nents, frmr->direction); svc_rdma_put_context(ctxt, 0); svc_rdma_put_frmr(xprt, frmr); return ret; } static unsigned int rdma_rcl_chunk_count(struct rpcrdma_read_chunk *ch) { unsigned int count; for (count = 0; ch->rc_discrim != xdr_zero; ch++) count++; return count; } /* If there was additional inline content, append it to the end of arg.pages. * Tail copy has to be done after the reader function has determined how many * pages are needed for RDMA READ. */ static int rdma_copy_tail(struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head, u32 position, u32 byte_count, u32 page_offset, int page_no) { char *srcp, *destp; int ret; ret = 0; srcp = head->arg.head[0].iov_base + position; byte_count = head->arg.head[0].iov_len - position; if (byte_count > PAGE_SIZE) { dprintk("svcrdma: large tail unsupported\n"); return 0; } /* Fit as much of the tail on the current page as possible */ if (page_offset != PAGE_SIZE) { destp = page_address(rqstp->rq_arg.pages[page_no]); destp += page_offset; while (byte_count--) { *destp++ = *srcp++; page_offset++; if (page_offset == PAGE_SIZE && byte_count) goto more; } goto done; } more: /* Fit the rest on the next page */ page_no++; destp = page_address(rqstp->rq_arg.pages[page_no]); while (byte_count--) *destp++ = *srcp++; rqstp->rq_respages = &rqstp->rq_arg.pages[page_no+1]; rqstp->rq_next_page = rqstp->rq_respages + 1; done: byte_count = head->arg.head[0].iov_len - position; head->arg.page_len += byte_count; head->arg.len += byte_count; head->arg.buflen += byte_count; return 1; } static int rdma_read_chunks(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head) { int page_no, ret; struct rpcrdma_read_chunk *ch; u32 handle, page_offset, byte_count; u32 position; u64 rs_offset; bool last; /* If no read list is present, return 0 */ ch = svc_rdma_get_read_chunk(rmsgp); if (!ch) return 0; if (rdma_rcl_chunk_count(ch) > RPCSVC_MAXPAGES) return -EINVAL; /* The request is completed when the RDMA_READs complete. The * head context keeps all the pages that comprise the * request. */ head->arg.head[0] = rqstp->rq_arg.head[0]; head->arg.tail[0] = rqstp->rq_arg.tail[0]; head->hdr_count = head->count; head->arg.page_base = 0; head->arg.page_len = 0; head->arg.len = rqstp->rq_arg.len; head->arg.buflen = rqstp->rq_arg.buflen; /* RDMA_NOMSG: RDMA READ data should land just after RDMA RECV data */ position = be32_to_cpu(ch->rc_position); if (position == 0) { head->arg.pages = &head->pages[0]; page_offset = head->byte_len; } else { head->arg.pages = &head->pages[head->count]; page_offset = 0; } ret = 0; page_no = 0; for (; ch->rc_discrim != xdr_zero; ch++) { if (be32_to_cpu(ch->rc_position) != position) goto err; handle = be32_to_cpu(ch->rc_target.rs_handle), byte_count = be32_to_cpu(ch->rc_target.rs_length); xdr_decode_hyper((__be32 *)&ch->rc_target.rs_offset, &rs_offset); while (byte_count > 0) { last = (ch + 1)->rc_discrim == xdr_zero; ret = xprt->sc_reader(xprt, rqstp, head, &page_no, &page_offset, handle, byte_count, rs_offset, last); if (ret < 0) goto err; byte_count -= ret; rs_offset += ret; head->arg.buflen += ret; } } /* Read list may need XDR round-up (see RFC 5666, s. 3.7) */ if (page_offset & 3) { u32 pad = 4 - (page_offset & 3); head->arg.tail[0].iov_len += pad; head->arg.len += pad; head->arg.buflen += pad; page_offset += pad; } ret = 1; if (position && position < head->arg.head[0].iov_len) ret = rdma_copy_tail(rqstp, head, position, byte_count, page_offset, page_no); head->arg.head[0].iov_len = position; head->position = position; err: /* Detach arg pages. svc_recv will replenish them */ for (page_no = 0; &rqstp->rq_pages[page_no] < rqstp->rq_respages; page_no++) rqstp->rq_pages[page_no] = NULL; return ret; } static void rdma_read_complete(struct svc_rqst *rqstp, struct svc_rdma_op_ctxt *head) { int page_no; /* Copy RPC pages */ for (page_no = 0; page_no < head->count; page_no++) { put_page(rqstp->rq_pages[page_no]); rqstp->rq_pages[page_no] = head->pages[page_no]; } /* Adjustments made for RDMA_NOMSG type requests */ if (head->position == 0) { if (head->arg.len <= head->sge[0].length) { head->arg.head[0].iov_len = head->arg.len - head->byte_len; head->arg.page_len = 0; } else { head->arg.head[0].iov_len = head->sge[0].length - head->byte_len; head->arg.page_len = head->arg.len - head->sge[0].length; } } /* Point rq_arg.pages past header */ rqstp->rq_arg.pages = &rqstp->rq_pages[head->hdr_count]; rqstp->rq_arg.page_len = head->arg.page_len; rqstp->rq_arg.page_base = head->arg.page_base; /* rq_respages starts after the last arg page */ rqstp->rq_respages = &rqstp->rq_pages[page_no]; rqstp->rq_next_page = rqstp->rq_respages + 1; /* Rebuild rq_arg head and tail. */ rqstp->rq_arg.head[0] = head->arg.head[0]; rqstp->rq_arg.tail[0] = head->arg.tail[0]; rqstp->rq_arg.len = head->arg.len; rqstp->rq_arg.buflen = head->arg.buflen; } /* By convention, backchannel calls arrive via rdma_msg type * messages, and never populate the chunk lists. This makes * the RPC/RDMA header small and fixed in size, so it is * straightforward to check the RPC header's direction field. */ static bool svc_rdma_is_backchannel_reply(struct svc_xprt *xprt, struct rpcrdma_msg *rmsgp) { __be32 *p = (__be32 *)rmsgp; if (!xprt->xpt_bc_xprt) return false; if (rmsgp->rm_type != rdma_msg) return false; if (rmsgp->rm_body.rm_chunks[0] != xdr_zero) return false; if (rmsgp->rm_body.rm_chunks[1] != xdr_zero) return false; if (rmsgp->rm_body.rm_chunks[2] != xdr_zero) return false; /* sanity */ if (p[7] != rmsgp->rm_xid) return false; /* call direction */ if (p[8] == cpu_to_be32(RPC_CALL)) return false; return true; } /* * Set up the rqstp thread context to point to the RQ buffer. If * necessary, pull additional data from the client with an RDMA_READ * request. */ int svc_rdma_recvfrom(struct svc_rqst *rqstp) { struct svc_xprt *xprt = rqstp->rq_xprt; struct svcxprt_rdma *rdma_xprt = container_of(xprt, struct svcxprt_rdma, sc_xprt); struct svc_rdma_op_ctxt *ctxt = NULL; struct rpcrdma_msg *rmsgp; int ret = 0; dprintk("svcrdma: rqstp=%p\n", rqstp); spin_lock_bh(&rdma_xprt->sc_rq_dto_lock); if (!list_empty(&rdma_xprt->sc_read_complete_q)) { ctxt = list_entry(rdma_xprt->sc_read_complete_q.next, struct svc_rdma_op_ctxt, dto_q); list_del_init(&ctxt->dto_q); spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock); rdma_read_complete(rqstp, ctxt); goto complete; } else if (!list_empty(&rdma_xprt->sc_rq_dto_q)) { ctxt = list_entry(rdma_xprt->sc_rq_dto_q.next, struct svc_rdma_op_ctxt, dto_q); list_del_init(&ctxt->dto_q); } else { atomic_inc(&rdma_stat_rq_starve); clear_bit(XPT_DATA, &xprt->xpt_flags); ctxt = NULL; } spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock); if (!ctxt) { /* This is the EAGAIN path. The svc_recv routine will * return -EAGAIN, the nfsd thread will go to call into * svc_recv again and we shouldn't be on the active * transport list */ if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) goto defer; goto out; } dprintk("svcrdma: processing ctxt=%p on xprt=%p, rqstp=%p, status=%d\n", ctxt, rdma_xprt, rqstp, ctxt->wc_status); atomic_inc(&rdma_stat_recv); /* Build up the XDR from the receive buffers. */ rdma_build_arg_xdr(rqstp, ctxt, ctxt->byte_len); /* Decode the RDMA header. */ rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base; ret = svc_rdma_xdr_decode_req(rmsgp, rqstp); if (ret < 0) goto out_err; if (ret == 0) goto out_drop; rqstp->rq_xprt_hlen = ret; if (svc_rdma_is_backchannel_reply(xprt, rmsgp)) { ret = svc_rdma_handle_bc_reply(xprt->xpt_bc_xprt, rmsgp, &rqstp->rq_arg); svc_rdma_put_context(ctxt, 0); if (ret) goto repost; return ret; } /* Read read-list data. */ ret = rdma_read_chunks(rdma_xprt, rmsgp, rqstp, ctxt); if (ret > 0) { /* read-list posted, defer until data received from client. */ goto defer; } else if (ret < 0) { /* Post of read-list failed, free context. */ svc_rdma_put_context(ctxt, 1); return 0; } complete: ret = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len + rqstp->rq_arg.tail[0].iov_len; svc_rdma_put_context(ctxt, 0); out: dprintk("svcrdma: ret=%d, rq_arg.len=%u, " "rq_arg.head[0].iov_base=%p, rq_arg.head[0].iov_len=%zd\n", ret, rqstp->rq_arg.len, rqstp->rq_arg.head[0].iov_base, rqstp->rq_arg.head[0].iov_len); rqstp->rq_prot = IPPROTO_MAX; svc_xprt_copy_addrs(rqstp, xprt); return ret; out_err: svc_rdma_send_error(rdma_xprt, rmsgp, ret); svc_rdma_put_context(ctxt, 0); return 0; defer: return 0; out_drop: svc_rdma_put_context(ctxt, 1); repost: return svc_rdma_repost_recv(rdma_xprt, GFP_KERNEL); }